416221 A7 經濟部智慧財產局員工消费合作社印製 B7 五、發明說明（/ ) 本發明之背景 1. 本發明之領域 本發明係有關於視頻顯示裝置之簾柵(screen)電壓’且 更特定的是有關於一種用於穩定化視頻顯示裝置之簾柵電 壓的電路，其能夠供應均一的簾柵電壓給該視頻顯示裝置 ，即使來自返馳變壓器的輸出電壓之電壓位準有所改變。 2. 習知技術之說明 一般而言，像是電腦系統的監視器之視頻顯示裝置係 回應一個同步信號來顯示來自外部的視頻信號於一登幕上 ，此係藉由將視頻信號與配置在陰極射線管的螢光幕上的 螢光物質撞擊來顯示。 爲了如上所述地顯示視頻信號於螢幕上’該視頻顯示 裝置必須用配置在陰極射線管中複數個柵(Srid)電極來依序 地執行控制、加速與聚焦該視頻信號的動作° 在此，該複數個柵電極具有一用以控制電子束的發射 量之第一柵電極、一用以控制該電子束的移動速度之第二 柵電極、一用以聚焦該電子束的第三柵電極、以及一用以 根據該電子束的移動而控制該電子束的擴散之第四柵電極 〇 在此時，被施加到該第二、第三與第四柵電極的電壓 係從返馳變壓器產生。於是，螢幕的亮度與品質是由該返 馳變壓器分別施加到該第二、第三與第四柵電極的電壓之 穩定度所決定。 爲了穩定化分別施加到該第二、第三與第四柵電極的 4 <請先閲讀背面之注意事項再填寫本頁) 線· 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公t ) 41622釔 A7 ____ B7 經濟部智慧財產局S工消費合作社印製 五、發明說明（2) 電壓，被輸入到該返馳變壓器的主要繞組之返馳脈衝的峰 値必須被維持在均一的電壓位準。 然而，返馳脈衝的峰値通常隨著感應到該返馳變壓器 的次要繞組之電壓的負載改變而改變β因此，感應到該返 馳變壓器的次要繞組之電壓位準係被改變。 於是’由於從該返馳變壓器分別被施加到該第二'第 三與第四柵電極的電壓’特別是被施加到該第二柵電極的 簾柵電壓之電壓位準被改變，故視頻顯示裝置之螢幕品質 係惡化。 本發明之槪要 因此’本發明之一目的係爲提供一種用於穩定化視頻 顯示裝置之簾柵電壓的電路，其能夠供應均一的簾柵電壓 給該視頻顯示裝置’即使來自返馳變壓器的輸出電壓之電 壓位準有所改變。 爲了達成以上的目的，本發明係提供一種用於穩定化 視頻顯示裝置之簾柵電壓的電路，其係包括： 水平輸出機構，其係用以回應於一個來自一外部的水 平驅動信號來產生一個水平輸出電壓； 返馳變壓器，其係用以根據該水平輸出電壓而從該外 部感應一第一電源至一主要繞組、依據一匝數比率(turn-ratio)感應出其之一次要繞組的電壓、並且用以根據該依據 前述的匝數比率被感應到該次要繞組的電壓來感應出其之 一第三繞組的電壓；以及 簾柵電壓產生機構，其係用以接收一第二電源以及一 5 (請先M讀背面之;i意事項再填窵本頁) • t 裝<-------訂· ！1 — ----線· 冬紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公蜚） 416222 a7 _____B7 五、發明說明（$ ) 個來自該外部的脈衝寬度調變信號、藉由回應於該脈衝寬 度調變信號以輸出或是切斷該第二電源’來控制被感應到 該返馳變壓器之第三繞組的電壓以維持—個均一的電壓位 準、並且用以輸出被感應到該第三繞組的電壓作爲簾柵電 壓。 根據本發明，從該返馳變壓器被施加到該第二柵電極 的簾柵電壓是藉由被感應到該返馳變壓器之第三繞組的電 壓所產生的。同時，即使該高電壓以及被感應到該第三繞 組的電壓被改變時，被感應到該返馳變壓器之第三繞組的 電壓仍係藉由控制該簾柵電壓產生部份而維持該均一的電 壓位準。於是，其能夠避免該視頻顯示裝置之螢幕亮度與 品質的惡化。 圖式之簡要說明 本發明上述的目的以及其它的優點將藉由參照所附的 圖式詳細地描述本發明之一個較佳的實施例而將變得更明 顯，其中： 圖1是顯示根據本發明之一實施例的用於穩定化視頻 顯示裝置之簾柵電壓的電路配置之方塊圖： 圖2是顯示圖1中所示的根據本發明之實施例的用於 穩定化視頻顯示裝置之簾柵電壓的電路之簾柵電壓產生部 份的配置之方塊圖； 圖3是顯示圖1中所示的根據本發明之實施例的用於 穩定化視頻顯示裝置之簾柵電壓的電路配置之電路圖；並 且 6 (請先閱讀背面之;tt.事項再填筠本頁) 裝------ 訂---------線 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用T國0家標準（CNS)A4規格（210x297公爱)_ A7 B7416221 A7 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economics B7 V. Description of the invention (/) Background of the invention 1. Field of the invention The invention relates to the screen voltage of a video display device and more specific The invention relates to a circuit for stabilizing the grid voltage of a video display device, which can supply a uniform grid voltage to the video display device even if the voltage level of the output voltage from the flyback transformer is changed. 2. Description of the conventional technology Generally speaking, a video display device such as a monitor of a computer system responds to a synchronization signal to display an external video signal on a screen. The fluorescent substance on the fluorescent screen of the cathode ray tube strikes to display. In order to display the video signal on the screen as described above, the video display device must use a plurality of grid electrodes arranged in a cathode ray tube to sequentially perform the actions of controlling, accelerating, and focusing the video signal. Here, The plurality of grid electrodes have a first grid electrode for controlling the emission amount of the electron beam, a second grid electrode for controlling the moving speed of the electron beam, a third grid electrode for focusing the electron beam, And a fourth grid electrode for controlling the diffusion of the electron beam according to the movement of the electron beam. At this time, the voltage applied to the second, third and fourth grid electrodes is generated from the flyback transformer. Therefore, the brightness and quality of the screen are determined by the stability of the voltages applied to the second, third, and fourth gate electrodes by the flyback transformer, respectively. In order to stabilize the 4 applied to the second, third, and fourth grid electrodes, < please read the precautions on the back before filling out this page) Line · This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297g t) 41622 Yttrium A7 ____ B7 Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, S Industrial Consumer Cooperative, V. Description of Invention (2) The voltage, the peak value of the flyback pulse input to the main winding of the flyback transformer must be maintained at Uniform voltage level. However, the peak value of the flyback pulse usually changes as the load of the secondary winding voltage induced to the flyback transformer changes β. Therefore, the voltage level of the secondary winding induced to the flyback transformer is changed. Thus, 'the voltage level of the curtain grid voltage applied to the second' third and fourth grid electrodes, in particular, from the flyback transformer, respectively, was changed, so the video display The screen quality of the device has deteriorated. The main purpose of the present invention is therefore 'an object of the present invention is to provide a circuit for stabilizing the grid voltage of a video display device, which is capable of supplying a uniform grid voltage to the video display device' even from a flyback transformer The voltage level of the output voltage has changed. In order to achieve the above object, the present invention provides a circuit for stabilizing the grid voltage of a video display device, which includes: a horizontal output mechanism for generating a horizontal driving signal in response to an external horizontal driving signal; Horizontal output voltage; Flyback transformer, which is used to induct a first power source to a main winding from the outside according to the horizontal output voltage, and induce the voltage of one of its secondary windings according to a turn-ratio And for sensing the voltage of one of the secondary windings according to the voltage of the secondary winding being induced according to the aforementioned turns ratio; and a grid voltage generating mechanism for receiving a second power source and 5 (please read the contents on the back; fill in this page first) • Packing < --------- Order ·! 1 — ---- line · Winter paper scale applies Chinese National Standard (CNS) A4 specification (210 X 297 cm) 416222 a7 _____B7 V. Description of the invention ($) Pulse width modulation signals from the outside, by Responding to the pulse width modulation signal to output or cut off the second power source to control the voltage induced to the third winding of the flyback transformer to maintain a uniform voltage level, and to output the induced voltage The voltage to this third winding is used as the grid voltage. According to the present invention, the grid voltage applied from the flyback transformer to the second grid electrode is generated by the voltage induced to the third winding of the flyback transformer. At the same time, even when the high voltage and the voltage induced to the third winding are changed, the voltage induced to the third winding of the flyback transformer still maintains the uniformity by controlling the grid voltage generating part. Voltage level. Therefore, it can avoid the deterioration of the screen brightness and quality of the video display device. BRIEF DESCRIPTION OF THE DRAWINGS The foregoing objects and other advantages of the present invention will become more apparent by describing a preferred embodiment of the present invention in detail with reference to the accompanying drawings, in which: FIG. A block diagram of a circuit configuration for stabilizing a curtain grid voltage of a video display device according to an embodiment of the present invention: FIG. 2 is a view showing a curtain for stabilizing a video display device according to an embodiment of the present invention shown in FIG. FIG. 3 is a circuit diagram showing a circuit configuration for stabilizing a grid voltage of a video display device according to an embodiment of the present invention shown in FIG. 1 ; And 6 (Please read the back; tt. Matters and then fill out this page) -------- Order --------- Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Applicable to 0 countries T standards (CNS) A4 specifications (210x297 public love) _ A7 B7
A1622A 五、發明說明（4) 圖4與圖5是顯示圖1中所示的根據本發明之實施例 的用於穩定化視頻顯示裝置之簾柵電壓的電路之固定電壓 開關部份的輸出電壓之波形圖。 在以下將參照該附圖來對於根據本發明之實施例的用 於保護視頻顯示裝置之突波(surge)電壓的電路之配置以及 動作做詳細的說明。 圖1是顯示根據本發明之一實施例的用於穩定化視頻 顯示裝置之簾柵電壓的電路配置之方塊圖。 參照圖1，該用於穩定化視頻顯示裝置之簾柵電壓的 電路係具有一個水平輸出部份100,其係用以回應於一個 來自一外部的水平驅動信號來輸出一個水平輸出電壓、一 個返馳變壓器FBT，其係用以根據該水平驅動信號而從該 外部感應一第一電源B+至一主要繞組L1、依據其之一匝 數比率而感應出其之次要繞組L2，L3與L4的電壓、並且 用以根據該依據前述的匝數比率被感應到該次要繞組的電 壓來感應出一第三繞組L5的電壓、一個高電壓輸出部份 Π0,其係用以根據該被感應到該返馳變壓器FBT的次要 繞組L2, L3與L4的電壓來分別供應一個聚焦電壓G3以及 —個高電壓G4至一個第三與一個第四柵電極(未顯示）、一 個簾柵電壓產生部份120,其係用以回應於一個第二電源 Vcc以及一個來自該外部的脈衝寬度調變信號PWM，來控 制被感應到該返馳變壓器FBT之第三繞組L5的電壓以維 持一個均一的電壓位準、並且用以供應被感應到該第三繞 _____ 7 (請先閱請背面之注意事項再填寫本頁) ^------ 訂---------線· 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 416221 at _____ B7 五、發明說明（i：) 組L5的電壓至一個第二柵電極(未顯示)作爲簾栅電壓G2 〇 圖2是顯示圖1中所示的根據本發明之實施例的用於 穩定化視頻顯示裝置之簾柵電壓的電路之簾柵電壓產生部 份的配置之方塊圖，並且圖3是顯示圖1中所示的根據本 發明之實施例的用於穩定化視頻顯示裝置之簾柵電壓的電 路配置之電路圖。 參照圖2 ’簾柵電壓產生部份120係具有一個簾柵電 壓供應部份123，其係用以整流被感應到返馳變壓器FBT 之第三繞組L5的電壓，以輸出一個整流後的電壓作爲簾 柵電壓G2、一個回授電阻器124，其係用以控制從簾柵電 壓供應部份123輸出的簾柵電壓G2，以維持該均一的電壓 位準、一個電流限制部份121，其係用以回應於脈衝寬度 調變信號PWM，來限制從回授電阻器U4輸出的輸出電壓 、一個固定電壓開關部份125，其係用以接收第二電源 Vcc’並且用以回應於來自該回授電阻器124的輸出電壓( 其電流係被電流限制部份121所限制)來輸出或是切斷第二 電源Vcc、以及一個電壓濾波部份122，其係用以濾掉來 自固定電壓開關部份125的輸出電壓之負電壓，以輸出一 個濾波後的電壓到返馳變壓器FBT之第三繞組L5。 參照圖3，簾柵電壓供應部份123係具有一個第一二 極體D1 ’其陽極與返馳變壓器fBT之第三繞組l5的一個 末端部份連接並且其陰極與回授電阻器124連接、以及一 個第一電容器C1，其一個末端部份係連接在第一二極體 8 4^4 ---11111 訂·--------"5^ ~ <請先閱讀背面之注.ΐ事項再填-«T本頁) 本紙張尺度適用中國國家標準（CNS)A.l規格（210 X 297公釐） 416222- A7 ---- B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（6 ) D1與回授電阻器124之間’而另一末端部份則爲接地。 固定電壓開關部份125是一個pnp型的電晶體Q2，其 係由一個接收第二電源Vcc的射極電極 個與電壓濾波 部份122連接之集極電極以及一個與回授電阻器124連接 之基極電極所組成》 同時，回授電阻器124具有第一、第二與第三電阻器 Rl’ R2與R3，其係依序地串聯在簾柵電壓供應部份123與 固定電壓開關部份125之間。 電壓濾波部份122係具有一個第四電阻器R4，其—個 末端部份係與pnp型的電晶體Q2之集極電極連接，而另 一末端部份則與返馳變壓器FBT之第三繞組L5的另一個 末立而部份連接、以及一個第二電容器C2 |其一個末端部份 係連接在第四電阻器R4與第三繞組L5的另一個末端部份 之間，而另一末端部份則爲接地。 此外’電流限制部份121係具有一個第五電阻器R5， 其一個末知部份係連接在回授電阻器124的第一電阻器R1 與pnp型的電晶體Q2之基極電極之間、—個第六電阻器 R6,其一個末端部份係與第五電阻器R5的另一個末端部 份連接，而其另一末端部份則爲接地、一個第七電阻器反7 ’其一個末端部份係連接在第五電阻器R5與第六電阻器 R6之間，而另一末端部份則接收脈衝寬度調變信號pwM 、以及一個第二電容器C3，其一個末端部份係與第七電阻 器R7的一個末端部份連接，而其另一末端部份則爲接地 〇 9 ------------'裝 ------- 訂---------- (請先Μ讀背面之注意事項再填¾本頁) 本紙張尺度適用τ國國豕標準（CNS)A4規格（210 X 297公爱） 416222 經濟部智慧財產局員工消費合作社印製 五、發明說明（1 ) 接著，水平輸出部份100係具有一個用以放大該水平 驅動信號之npn型的電晶體Q1、一個用以根據npn型的電 晶體Q1的開關動作來反覆地進行充放電動作以產生一個 鋸齒波信號之電容器CT、一個用以根據該鋸齒波信號來產 生偏向力以將電子束於水平方上偏向之水平偏向線圈Ldy 、以及一個以一種S型的形式用以補償該鋸齒波信號之電 容器Cs。 以下，根據本發明之實施例的用於穩定化視頻顯示裝 置之簾柵電壓的電路動作係加以詳細說明。 圖4是顯示當脈衝寬度調變信號PWM之電壓位準爲 高位準時，從pnp型的電晶體Q2之集極電極輸出的輸出 電壓之波形圖，而圖5是顯示當脈衝寬度調變信號PWM 之電壓位準爲低位準時，從pnp型的電晶體Q2之集極電 極輸出的輸出電壓之波形圖。 首先，當水平輸出部份100之ηρη型的電晶體Q1回 應於該水平驅動信號而被導通時，一個依據該第一電源Β+ 的第一電壓被感應到返馳變壓器FBT的主要繞組U。 當一個依據匝數比率的第二電壓藉由被感應到返馳變 壓器FBT的主要繞組L1之第一電壓而被感應到返馳變壓 器FBT的次要繞組L2, L3與L4時，高電壓部份110分別 供應聚焦電壓G3以及高電壓G4至該第三與第四柵電極( 未顯示）。 * 在此時，參考圖號D3, D4, D5與D6分別是一個用於 阻斷反向電流的二極體、參考圖號RH是一個用於高電壓的 10 -- (請先閱讀背面之注意事項再填寫本頁) -*·έA1622A V. Description of the invention (4) Figures 4 and 5 show the output voltage of the fixed voltage switch section of the circuit for stabilizing the grid voltage of the video display device according to the embodiment of the present invention shown in Figure 1 Waveform diagram. The configuration and operation of a circuit for protecting a surge voltage of a video display device according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing a circuit configuration for stabilizing a grid voltage of a video display device according to an embodiment of the present invention. Referring to FIG. 1, the circuit for stabilizing the grid voltage of a video display device has a horizontal output section 100, which is used to output a horizontal output voltage and a return voltage in response to a horizontal drive signal from an external source. The FBT transformer is used to induct a first power source B + to a main winding L1 from the outside according to the horizontal driving signal, and to sense its secondary windings L2, L3 and L4 according to one of its turns ratios. Voltage, and is used to induce the voltage of a third winding L5 and a high voltage output part Π0 according to the voltage of the secondary winding induced according to the aforementioned turns ratio, which is used to be induced according to the The voltages of the secondary windings L2, L3 and L4 of the flyback transformer FBT supply a focus voltage G3 and a high voltage G4 to a third and a fourth grid electrode (not shown), and a grid voltage generating section, respectively. Part 120, which is used to control the voltage induced in the third winding L5 of the flyback transformer FBT in response to a second power source Vcc and a pulse width modulation signal PWM from the outside. A uniform voltage level and used to supply the third winding _____ 7 (Please read the precautions on the back before filling this page) ^ ------ Order ------- --Line · Printed by the Employees 'Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper is printed in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economy Explanation (i :) The voltage of the group L5 to a second grid electrode (not shown) is used as the grid voltage G2. Block diagram of the configuration of the grid voltage generating section of the grid voltage circuit, and FIG. 3 is a circuit configuration showing the grid voltage for stabilizing the grid voltage of the video display device according to the embodiment of the present invention shown in FIG. 1 Circuit diagram. Referring to FIG. 2 'The grid voltage generating part 120 has a grid voltage supply part 123, which is used to rectify the voltage induced to the third winding L5 of the flyback transformer FBT to output a rectified voltage as The grid voltage G2 and a feedback resistor 124 are used to control the grid voltage G2 output from the grid voltage supply section 123 to maintain the uniform voltage level. A current limiting section 121 is In response to the pulse width modulation signal PWM to limit the output voltage output from the feedback resistor U4, a fixed voltage switching section 125 is used to receive the second power source Vcc 'and to respond to the voltage from the feedback The output voltage of the resistor 124 (the current of which is limited by the current limiting portion 121) is used to output or cut off the second power source Vcc, and a voltage filtering portion 122 is used to filter out the voltage from the fixed voltage switching portion. The negative voltage of the output voltage of part 125 is used to output a filtered voltage to the third winding L5 of the flyback transformer FBT. Referring to FIG. 3, the grid voltage supply portion 123 has a first diode D1 'whose anode is connected to one end portion of the third winding 15 of the flyback transformer fBT and whose cathode is connected to the feedback resistor 124. And a first capacitor C1, one end part of which is connected to the first diode 8 4 ^ 4 --- 11111 Order · -------- " 5 ^ ~ < Please read the back Note. Please re-fill the matter-«T page) This paper size is applicable to the Chinese National Standard (CNS) Al specification (210 X 297 mm) 416222- A7 ---- B7 Printed by the Staff Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 6. Description of the invention (6) Between D1 and the feedback resistor 124 'and the other end portion is grounded. The fixed voltage switching section 125 is a pnp-type transistor Q2, which is composed of an emitter electrode receiving the second power source Vcc, a collector electrode connected to the voltage filtering section 122, and a collector electrode connected to the feedback resistor 124. Composition of the base electrode "At the same time, the feedback resistor 124 has first, second and third resistors R1 ', R2 and R3, which are connected in series to the curtain voltage supply part 123 and the fixed voltage switch part. Between 125. The voltage filtering part 122 has a fourth resistor R4, one end part of which is connected to the collector electrode of the pnp transistor Q2, and the other end part is connected to the third winding of the flyback transformer FBT. Another terminal part of L5 is connected, and a second capacitor C2 | One terminal part is connected between the fourth resistor R4 and the other terminal part of the third winding L5, and the other terminal part Shares are grounded. In addition, the current limiting portion 121 has a fifth resistor R5, and a last-known portion is connected between the first resistor R1 of the feedback resistor 124 and the base electrode of the pnp-type transistor Q2, A sixth resistor R6, one end portion of which is connected to the other end portion of the fifth resistor R5, and the other end portion of which is grounded, and a seventh resistor inverse 7 'one end Part is connected between the fifth resistor R5 and the sixth resistor R6, and the other end part receives the pulse width modulation signal pwM and a second capacitor C3, and one end part is connected to the seventh One end of the resistor R7 is connected, and the other end of the resistor R7 is grounded. 9 ------------ 'Installation ------- Order ------ ---- (Please read the notes on the back before filling this page ¾) This paper size is applicable to τ National Standard (CNS) A4 (210 X 297 public love) 416222 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs System V. Description of the Invention (1) Next, the horizontal output section 100 has an npn transistor Q1 for amplifying the horizontal driving signal. A capacitor CT for repeatedly charging and discharging to generate a sawtooth wave signal based on the switching action of the npn-type transistor Q1, and a capacitor CT for generating a biasing force based on the sawtooth wave signal to place the electron beam horizontally The biased horizontally biased coil Ldy and a capacitor Cs in an S-shaped form are used to compensate the sawtooth wave signal. Hereinafter, the operation of the circuit for stabilizing the grid voltage of the video display device according to the embodiment of the present invention will be described in detail. FIG. 4 is a waveform diagram showing the output voltage output from the collector electrode of the pnp transistor Q2 when the voltage level of the pulse width modulation signal PWM is high, and FIG. 5 is a diagram showing the output voltage when the pulse width modulation signal PWM Waveform diagram of the output voltage output from the collector electrode of the pnp-type transistor Q2 when the voltage level is low. First, when the ηρη-type transistor Q1 of the horizontal output part 100 is turned on in response to the horizontal driving signal, a first voltage according to the first power source B + is induced to the main winding U of the flyback transformer FBT. When a second voltage according to the turns ratio is induced to the secondary windings L2, L3 and L4 of the flyback transformer FBT by the first voltage induced to the primary winding L1 of the flyback transformer FBT, the high voltage portion 110 supplies a focus voltage G3 and a high voltage G4 to the third and fourth grid electrodes (not shown), respectively. * At this time, the reference figure numbers D3, D4, D5 and D6 are respectively a diode for blocking reverse current, and the reference figure number RH is a 10 for high voltage-(Please read the (Please fill in this page again)-* · έ
X 本紙張尺度適用中國國家標準（CNS>A4規格（2〗0»297公釐） A7 A7 B7 416^2=-- 五、發明說明（8 ) 電阻器、並且參考圖號VR1是一個用於聚焦電壓的可變電 阻。 (請先閲讀背面之it意事項再填寫本頁) 接著，一個第三電壓係藉由被感應到返馳變壓器FBT 的次要繞組L2, L3與L4之第二電壓而被感應到返馳變壓 器FBT的第三繞組L5 ’並且該第三電壓被用作爲簾柵電 壓G2。 —般而言，簾柵電壓G2係以400至700伏特被施加 到螢幕’並且被感應到返馳變壓器FBT的第三繞組L5之 第三電壓的振幅被維持在800Vp-p。 該第三電壓藉由簾柵電壓供應部份123的第一二極體 D1以及第一電容器C1而被整流，並且被供應到該第二柵 電極(未顯示）。 從一個微電腦(未顯示)輸出的脈衝寬度調變信號PWM 係藉由第六與第七電阻器R6與R7分壓，並且藉由第三電 容器C3加以平流化。同時，脈衝寬度調變信號PWM係限 制經由第五電阻器R5被施加到pnp型的電晶體Q2的基極 電極之電流。 經濟部智慧时產局員工消費合作社印製 在此時，如圖4中所示，當具有相當於5伏特的高電 壓之脈衝寬度調變信號PWM被施加到電流限制部份121 時’ pnp型的電晶體Q2係被關斷，並且其集極電極的負電 壓被維持在大約150至200伏特。於是，由於被第一二極 體D1以及第一電容器C1整流的電壓位準變低，故簾柵電 壓G2下降。 相反地’如圖5中所示，當具有相當於〇伏特的低電 本纸張尺度適用中S國家標準（CNS)A4規格（210 X 297公楚） 416222 A7 B7 t 經濟部智慧財產局員x消費合作社印製 五、發明說明（？） 壓之脈衝寬度調變信號PWM被施加到電流限制部份121 時，pnp型的電晶體Q2係被導通*並且來自其集極電極的 第二電源Vcc被施加到電壓濾波部份122 〇於是，由於被 第一二極體D1以及第一電容器C1整流的電壓位準變高， 故簾柵電壓G2上升。 換言之，如圖4與5中所示，簾栅電壓G2可以根據 被脈衝寬度調變信號PWM所控制之pnp型的電晶體Q2 的基極電流而被設定成爲所要的電壓位準。 在此時，設定後的簾柵電壓G2係藉由返馳變壓器 FBT之第三電壓以及第一電源B+之電壓位準的變化而加以 改變。 換言之，當被第一二極體D1以及第一電容器C1所整 流的簾柵電壓G2的電壓位準因爲一個負載的改變而上升 時，由回授電阻器124之具有高阻抗的第一、第二與第三 電阻器Rl，R2與R3所檢測到的電流係增加pnp型的電晶 體Q2的基極電流。 於是，由於pnp型的電晶體Q2維持關斷的狀態，並 且來自pnp型的電晶體Q2之集極電極且被施加到電壓濾 波部份122之輸出電壓係具有負的電位，故依據負載的改 變而增加之簾柵電壓G2的電壓位準係下降。 相反地，當被第一二極體ΓΜ以及第一電容器C1所整 流的簾栅電壓G2的電壓位準因爲一個負載的改變而下降 時，由回授電阻器124之具有高阻抗的第一、第二與第三 電阻器Rl，R2與R3所檢測到的電流係減少pnp型的電晶 <請先閱讀背面之注意事項再填寫本頁)X This paper size applies to Chinese national standards (CNS > A4 specifications (2〗 0 »297 mm) A7 A7 B7 416 ^ 2 =-V. Description of the invention (8) Resistors and reference number VR1 is a Variable resistor focusing voltage. (Please read the notice on the back before filling this page.) Next, a third voltage is the second voltage of the secondary windings L2, L3 and L4 of the flyback transformer FBT. The third winding L5 'of the flyback transformer FBT is induced and this third voltage is used as the grid voltage G2. Generally, the grid voltage G2 is applied to the screen at 400 to 700 volts and is sensed The amplitude of the third voltage to the third winding L5 of the flyback transformer FBT is maintained at 800 Vp-p. This third voltage is passed through the first diode D1 and the first capacitor C1 of the grid voltage supply section 123. It is rectified and supplied to the second gate electrode (not shown). The pulse width modulation signal PWM output from a microcomputer (not shown) is divided by the sixth and seventh resistors R6 and R7, and by the The third capacitor C3 is smoothed. At the same time, the pulse width modulation signal The PWM system limits the current applied to the base electrode of the pnp-type transistor Q2 via the fifth resistor R5. The employee consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed at this time, as shown in FIG. When a high-voltage pulse width modulation signal PWM of 5 volts is applied to the current limiting portion 121, the pnp-type transistor Q2 is turned off, and the negative voltage of its collector electrode is maintained at about 150 to 200 volts. Therefore, since the voltage level rectified by the first diode D1 and the first capacitor C1 becomes low, the grid voltage G2 decreases. Conversely, as shown in FIG. 5, when a low voltage equivalent to 0 volts is present This paper size applies to the national S (CNS) A4 specification (210 X 297 Gongchu) 416222 A7 B7 t Member of the Intellectual Property Bureau of the Ministry of Economic Affairs x Printed by Consumer Cooperatives 5. Description of the invention (?) Pulse width modulation signal PWM When applied to the current limiting portion 121, the pnp-type transistor Q2 is turned on * and the second power source Vcc from its collector electrode is applied to the voltage filtering portion 122. Therefore, due to the first diode D1 And the first capacitor C1 is rectified The voltage level becomes higher, so the grid voltage G2 rises. In other words, as shown in FIGS. 4 and 5, the grid voltage G2 can be based on the base of the pnp-type transistor Q2 controlled by the pulse width modulation signal PWM. The current is set to the desired voltage level. At this time, the set grid voltage G2 is changed by changing the third voltage of the flyback transformer FBT and the voltage level of the first power source B +. In other words, When the voltage level of the grid voltage G2 rectified by the first diode D1 and the first capacitor C1 rises due to a change in load, the first, second and The current detected by the third resistors R1, R2 and R3 increases the base current of the pnp-type transistor Q2. Therefore, since the pnp-type transistor Q2 is maintained in an off state, and the output voltage from the collector electrode of the pnp-type transistor Q2 and applied to the voltage filtering section 122 has a negative potential, it depends on the load change. The voltage level of the increased grid voltage G2 decreases. Conversely, when the voltage level of the grid voltage G2 rectified by the first diode ΓM and the first capacitor C1 decreases due to a change in load, the first, (The currents detected by the second and third resistors R1, R2, and R3 are reduced pnp-type transistors. <Please read the precautions on the back before filling this page.)
裝--— — — It — 訂-----I--•線 V 本纸張尺度適用中囷國家標準（CNS)A4規格·（210x297公釐） 416221 B7 五、發明說明（β ) 體Q2的基極電流 於是，由於ρηρ型的電晶體Q2維持導通的狀態，並 且第二電源Vcc係從ρηρ型的電晶體Q2之集極電極輸出 ，且第二電源Vcc被施加到電壓濾波部份122，故依據負 載的改變而減少之簾柵電壓G2的電壓位準係上升。 在上述的根據本發明之用於穩定化視頻顯示裝置之簾 栅電壓的電路中，從返馳變壓器施加到該第二柵電極的簾 柵電壓係藉由被感應到返馳變壓器的第三繞組之電壓來加 以產生。 同時，被感應到返馳變壓器的第三繞組之電壓係藉由 控制該簾柵電壓產生部份而維持該均一的電壓位準，即使 該高電壓以及被感應到該第三繞組的電壓有所改變。 於是，其能夠避免該視頻顯示裝置之螢幕亮度與品質 的惡化。 雖然本發明已經參照一個特定的實施例來特定地顯示 與描述，但熟習此項技術者將可理解的是各種在形式與細 節上的變化可以在不脫離由所附的申請專利範圍所定義之 本發明的精神與範疇之下加以達成。 lllll — llt— — — * I I I ! I I I + IIIJI — — · (請先間讀背面之法意事項再填寫本頁) 规濟部智慧財產局員工消費合作社印製 各紙張尺度適用中®國家標準（CNS)A4規格（210x 297公釐）Loading --- — — It — Order ----- I-- • Line V This paper size is applicable to China National Standard (CNS) A4 specifications (210x297 mm) 416221 B7 V. Description of invention (β) The base current of Q2 is therefore because the ρηρ-type transistor Q2 remains on, and the second power source Vcc is output from the collector electrode of the ρηρ-type transistor Q2, and the second power source Vcc is applied to the voltage filtering portion 122, so the voltage level of the grid voltage G2, which is reduced according to the change of the load, is increased. In the above-mentioned circuit for stabilizing the grid voltage of a video display device according to the present invention, the grid voltage applied from the flyback transformer to the second grid electrode is induced to the third winding of the flyback transformer. Voltage. At the same time, the voltage of the third winding induced to the flyback transformer is maintained at the uniform voltage level by controlling the grid voltage generating part, even if the high voltage and the voltage induced to the third winding are somewhat different. change. Therefore, it can avoid the deterioration of the screen brightness and quality of the video display device. Although the present invention has been specifically shown and described with reference to a specific embodiment, those skilled in the art will understand that various changes in form and details can be made without departing from the scope defined by the appended patents. This is achieved within the spirit and scope of the present invention. lllll — llt — — — * III! III + IIIJI — — (Please read the legal notices on the back before filling out this page) The Intellectual Property Bureau Staff Consumer Cooperatives of the Ministry of Economic Affairs printed various paper standards applicable to the national standards ( CNS) A4 size (210x 297 mm)